颗粒体病毒在小菜蛾种群中的垂直传播方式的初步观察

在室内观察了小菜蛾颗粒体病毒PlutellaxylostellaGranulosisVirus(RxGV)在小菜蛾种群水平上可能的垂直传播途径。结果表明 :(1 )上代小菜蛾Plutellaxylostella(L .)幼虫期饲毒不能将小菜蛾颗粒体病垂直传递到下代 ;(2 )取食病毒的雌蛾产的卵所孵化的幼虫中 ,没病毒感染出现 ,说明病毒不能经小菜蛾成虫体内传播到下一代。 (3 )用小菜蛾颗粒体病毒处理卵卡时 ,其初孵幼虫有少量被病毒感染死亡 ,浓度高时感染率也较高 ,但感染率均在 1 0 %以下 ,说明小菜蛾颗粒体病毒能经卵表垂直传递给下代 ,但传递效率不高。但当用病毒处理叶片上的卵时 ,初孵幼虫死亡率高达 77 73 % ,而且孵化出的幼虫大多数染病且死于 3龄以前 ,因此田间病毒的施用时间可提早到卵高峰期。     

Suppressor genes with gender differences in activity in natural populations of Drosophila robusta: another approach to wild-type

Homozygous or hemizygous expression of an X-linked wing mutant of Drosophila robusta varies from a rudimentary wing that does not reach the tip of the abdomen (called 'club') to forms with full-sized but curled or crumpled wings (called 'curly'). Homozygous club females crossed to flies from natural populations or laboratory stocks derived from wild flies invariably produce significantly less club male progeny than the 100% expected, most of them exhibiting less severe phenotypes: 'curly' forms and wild-type. The male progeny from similar crosses using curly females tend to be predominantly normal. By contrast, the male progeny of outcrossed females homozygous for an X-linked eye colour mutant, vermilion, are all vermilion. The data indicate that natural populations of D. robusta contain suppressors of the wing mutant but not of the eye colour mutant studied. Activity of the suppressors differs by gender: in experiments in which genetic theory expects similar results in the two sexes, males consistently show stronger effects of the suppressors than females.     

Sire effect on early and late embryonic death in French Holstein cattle

We investigated the effect of maternal sire on early pregnancy failure (between D0, day of insemination and D90) in their progeny during the first and second lactations (n=3508) in the Holstein breed. The estimated breeding value (EBV) for cow fertility of 12 bulls (reliability⩾0.95) was used to create the following three groups: low, medium and high EBV (EBV from −0.7 to 1 expressed as genetic standard deviation relative to the mean of the breed). In their daughters (93 to 516 per bull), progesterone measurement was carried out on the day of artificial insemination (AI; D0) to check whether the cows were in the follicular phase and on D18 to 25 to assess non-fertilisation-early embryonic mortality (NF-EEM). Late embryonic mortality (LEM) and early foetal death (FD) were determined by ultrasonography on D45 and D90 and by the return to oestrus after the first AI. Frequencies of NF-EEM, LEM, FD and pregnancy were 33.3%, 11.7%, 1.4% and 48.5% and incidences were 35.1, 19.0, 2.7 and 51.1, respectively. Sire EBV was significantly related to the incidences of pregnancy failure between D0 and D90, fertilisation failure-early embryonic mortality (FF-EEM) and LEM but not to the incidence of FD between D45 and D90 of pregnancy. The relative risk (RR) of FF-EEM was significantly higher (RR=1.2; P<0.05) for the progeny group of low EBV bulls when compared with high EBV bulls. The same effect was observed when comparing LEM of the progeny groups from the low EBV bulls to those from moderate and high EBV bulls (RR, respectively, of 1.3 and 1.4; P<005). The incidence of FF-EEM was significantly higher when cows were inseminated before 80 days postpartum compared with later, and for the extreme values of the difference between milk fat and protein content measured during the first 3 months of lactation. FF-EEM was also significantly related to the year of observation. The incidence of LEM was higher for the highest producing cows and was influenced by interaction between milk yield×lactation rank and milk yield×milk protein content. In conclusion, this study showed large differences in early pregnancy failure between progeny groups and highlights the interest of accurate characterisation of embryonic death in order to identify potential candidate genes for female fertility.     

The role of seed-tuber and stem inoculum in the development of gangrene in potatoes

To determine the relative importance of seed tubers and stems as sources of inoculum for potato gangrene in progeny tubers, different levels of inoculum of Phoma exigua var. foveata were established in field experiments by planting rotting or contaminated seed tubers and by inoculating stems shortly before haulm desiccation. The pathogen was only occasionally detected by isolation from inside green stems in June and July on plants growing from contaminated but unrotted seed. The incidence of pycnidia on desiccated stems increased with increasing concentration of inoculum contaminating seed tubers and with increasing time interval between desiccation and harvest. Stem infection was probably derived from inoculum on seed tubers spreading via the soil to the stem bases. Stem inoculation of plants growing from uninoculated or uncontaminated seed greatly increased both the gangrene potential of progeny tubers (defined as % wounds with gangrene after uniformly damaging tubers and storing them at 5°C for 12 wk), and tuber contamination (defined as % wounds with gangrene after spreading tuber-borne soil onto test tuber slices and storing them at 5°C for 8 wk). However, when stems of plants growing from rotting or contaminated seed were cut at ground level and removed before desiccation, gangrene potential of progeny tubers was only slightly less than that of tubers from untreated plots. There was no evidence that soil inoculum or aerial spread played a significant role in disease development. Gangrene potential and contamination of progeny tubers were related to Contamination levels on seed tubers. Some transmission also occurred from rotted seed tubers to progeny. Inoculum levels around progeny tubers increased rapidly after desiccation even in plots where stems had previously been cut at soil level and removed to eliminate pycnidial development above ground as a source of inoculum. Both gangrene potential and contamination of progeny tubers were greater on cv. Ulster Sceptre than on cv. Pentland Crown. The results showed that the inoculum on seed tubers, whether from rots or surface contamination, contributed more to the contamination of progeny tubers at harvest than did the inoculum from pycnidia on stems following desiccation of the haulm.     

The effect of gypsy moth metamorphosis on the development of nuclear polyhedrosis virus infection

The development of nuclear polyhedrosis virus (NPV) infection in gypsy moth (Lymantria dispar) was studied before, during, and after host metamorphosis, and in larvae and pupae in the subsequent generation, to determine whether NPV ingested by late instars can replicate in host tissues through metamorphosis and whether it can be vertically transmitted to progeny. Individuals that survived sublethal dosages of NPV did not differ from undosed insects in pupal weight, fecundity, larval and pupal weight of progeny, or response of progeny to NPV challenge. No evidence of NPV infection or of abnormal histology was found in adult tissues examined by light microscopy and no virus was detected on the surface of eggs produced by NPV-treated moths. No NPV-caused mortality was recorded among undosed progeny of dosed or undosed parents. The progeny of dosed parents were neither more resistant nor more susceptible to LdMNPV than were progeny of undosed parents and lethal times did not differ between groups. Examination of larval, pupal, and adult tissues by DNA hybridization revealed that insects in which NPV DNA was detected died prior to adult eclosion. NPV was not detected in any hosts surviving to the adult stage. These results suggest that survivors of sublethal dosages of NPV avoid infection and are therefore incapable of vertically transmitting infectious virus to progeny.     

Cricket Paralysis Virus, a Potential Control Agent for the Olive Fruit Fly, Dacus oleae Gmel

Representatives of several families of insect viruses were tested for growth and pathogenicity in the olive fruit fly, Dacus oleae Gmel. The viruses included nuclear polyhedrosis viruses, an iridovirus, two picornaviruses, and Trichoplusia ni small RNA virus (a member of the Nudaurelia β family), in addition to two naturally occurring viruses of the olive fruit fly. Two viruses, one of the two picornaviruses (cricket paralysis virus [CrPV] and the iridovirus (type 21 from Heliothis armigera), were found to replicate in adult flies. Flies which were fed on a solution containing CrPV for 1 day demonstrated a high mortality with 50% dying within 5 days and nearly 80% dying within 12 days of being fed. The virus was transmissible from infected to noninfected flies by fecal contamination. The CrPV which replicated in the infected flies was demonstrated to be the same as input virus by infection of Drosophila melanogaster cells and examination of the expressed viral proteins, immunoprecipitation of the virus purified from flies, and electrophoretic analysis of the structural proteins.     

The effects of serial passage of a nucleopolyhedrosis virus through an alternate host system

The multiple-embedded velvetbean caterpillar nucleopolyhedrosis virus (VBC-NPV) ofAnticarsia gemmatalis Hübner was shown to be infectious of a variety of noctuid hosts. The mortality data demonstrated the importance of defining the dosage used in host range analysis. Serial passage of the VBC-NPV through the soybean looper,Pseudoplusia includens, was done to select for host range variants of this NPV. After several passages of the VBC-NPV through this insect the virulence of the progeny virus remained unchanged indicating heterogeneity in the host and not the virus population. However, between the 3rd and 5th serial passage throughPseudoplusia a latent NPV identical to a single-embedded NPV previously associated fromA. gemmatalis was activated. The biological and biochemical characteristics of this isolate demonstrated it to be distinct from the original VBC-NPV. A single passage of this activated virus throughA. gemmatalis resulted in the production of viral progeny having characteristics of the original VBC-NPV. Serial passage of this virus preparation throughP. includens resulted in virus progeny having biological properties associated with both the original VBC-NPV and the activated NPV isolate.     

Feeding dried distillers grains with solubles to lactating beef cows: impact of excess protein and fat on cow performance,milk production and pre-weaning progeny growth

Multiparous Angus×Simmental cows (n=54, 5.22±2.51 years) with male progeny were fed one of two diets supplemented with either dried distillers grains with solubles (DDGS) or soybean meal (CON), from calving until day 129 postpartum (PP) to determine effects of excess protein and fat on cow performance, milk composition and calf growth. Diets were formulated to be isocaloric and consisted of rye hay and DDGS (19.4% CP; 8.76% fat), or corn silage, rye hay and soybean meal (11.7% CP; 2.06% fat). Cow–calf pairs were allotted by cow and calf age, BW and breed. Cow BW and body condition score (BCS; P⩾0.13) were similar throughout the experiment. A weigh-suckle-weigh was performed on day 64 and day 110±10 PP to determine milk production. Milk was collected on day 68 and day 116±10 PP for analysis of milk components. Milk production was unaffected (P⩾0.75) by dietary treatments. Milk urea nitrogen was increased at both time points in DDGS compared with CON cows (P<0.01). Protein was decreased (P=0.01) and fat was increased (P=0.01) in milk from DDGS compared with CON cows on day 68 PP. Compared to CON, DDGS decreased medium chain FA (P<0.01) and increased long chain FA (P<0.01) at both time points. Saturated FA content of milk was decreased (P<0.01) at both time-points in DDGS compared with CON cows, which resulted in an increase (P<0.01) in monounsaturated and polyunsaturated FA, including cis-9, trans-11 conjugated linoleic acid. Daily gain of the DDGS calves was increased (P=0.01) compared with CON calves, resulting in heavier BW on day 129 (P=0.01). Heavier BW of DDGS calves was maintained through weaning (P=0.01). Timed-artificial insemination (TAI) rates were greater for cows fed DDGS compared with cows fed CON (P<0.02), but dietary treatment had no effect on overall pregnancy rates (P=0.64). In summary, feeding DDGS to lactating beef cows did not change cow BW or BCS, but did improve TAI rates and altered milk composition compared with CON. As a result, male progeny from cows fed DDGS during lactation had greater average daily gain and were heavier at day 129 and at weaning compared with male progeny from cows fed a control diet.     

甜菜夜蛾核型多角体病毒在宿主种群中的垂直传播研究

以两种浓度的病毒液感染甜菜夜蛾4龄、5龄幼虫,以研究甜菜夜蛾核型多角体病毒从亲代到子代垂直传递的方式和效率。实验结果表明,该病毒可通过母体介导(卵内、卵表)和父体介导等3种方式传递给子代,造成子代感染。幼虫经口感染后母体介导传递实验表明,病毒垂直传播可引起20%～48%的子代幼虫病死,并能使子代成虫产卵量下降;母体介导传播实验中,以5%福尔马林进行卵表面消毒证实仍有18.8%的幼虫感染病毒死亡,表明了该病毒可经卵内传播,并同时存在着附卵传播;母体介导传递实验还表明病毒对宿主有弱化作用,亲代免于病死的蛹重量减轻,羽化所得雌成虫的产卵量下降,产卵期延长。以交互配对将感染与未感染的雌雄成虫彼此交配,表明雄成虫精子也能垂直传递病毒(父体介导),引起20％～40%子代幼虫感病死亡。成虫经口感染,对所产卵块表面消毒后,仍导致28.6%的子代幼虫死于病毒感染,也表明存在卵内传播。     

Paternity following multiple mating in ladybird <Emphasis Type="Italic">Harmonia axyridis</Emphasis>

We investigated factors which may determine realised paternity following multiple mating in a promiscuous ladybird Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), namely the mating order and ability of males of different morphs to fertilize females. In experiments using males of two colour morphs, we found that the first male had a reproductive advantage over the second male (sperm precedence P2 = 0.38). Males of the melanic morph spectabilis had a reproductive advantage over males of the semi-melanic morph axyridis (P2 = 0.35). Analysis of paternity using microsatellites applied to young larvae, which avoids possible differential mortality of progeny, confirmed the precedence of the first male and higher paternity rate of colour morphs that are more frequent in the wild. Hatchability of eggs increased from 65% after the first mating to 85% after the second mating delayed by five days. Average duration of mating was 157 min and did not differ between the first and second mating and between the colour morphs of males.     

Effect of temperature and commodity on insecticidal efficacy of spinosad dust against Sitophilus oryzae (Coleoptera: Curculionidae) and Rhyzopertha dominica (Coleoptera: Bostrychidae)

The insecticidal effect of spinosad dust, a formulation that contains 0.125% spinosad, was evaluated against adults of Sitophilus oryzae (L.) and Rhyzopertha dominica (F.) at three temperature levels (20, 25, and 30 degrees C) and four commodities (wheat, Triticum aestivum L.; barley, Hordeum vulgare L.; rice, Oryza sativa L.; and maize, Zea mays L.). For this purpose, quantities of the above-mentioned grains were treated with spinosad at two dose rates (20 and 50 ppm of the formulation, corresponding to 0.025 and 0.06 ppm AI, respectively), and mortality of the exposed adults in the treated grains was measured after 7 and 14 d, whereas progeny production was assessed 65 d later. Generally, for both species, mortality increased with dose, exposure interval, and temperature. For S. oryzae, adult survival and progeny production were lower on wheat than the other grains. After 14 d of exposure, mortality of S. oryzae adults on wheat treated with 50 ppm ranged between 61 and 98%, whereas in the other three commodities it did not exceed 42%. Mortality of R. dominica after 14 d on grains treated 50 ppm ranged between 91 and 100%. For this species, progeny production from exposed parental adults was low in all commodities regardless of temperature. Results indicate that spinosad dust can be used as an alternative to traditional grain protectants, but its effectiveness is highly determined by the target species, commodity, dose, and temperature.     

Life History of Bracon hebetor (Hymenoptera: Braconidae) on Plodia interpunctella (Lepidoptera: Pyralidae) on a Dried Vegetable Commodity

Life history of Bracon hebetor Say was studied on Plodia interpunctella Hübner. The life span of female (mean±s.e.) was estimated to be 20.88±0.97 days. The females laid eggs from the first day on after emergence and the oviposition period ranged from 11 to 27 days. But 65% of the total eggs were laid in the first 10 days. The progeny sex ratio (female/total) in the first 15 days was female-bias ranged from 0.51±0.08 to 0.88±0.02, but changed into male-bias ranged from 0.14±0.04 to 0.34±0.12. The overall sex ratio of progeny produced per female was estimated to be 0.66. Total number of progeny per female and net reproduction rate were estimated to be 205.17±13.03 and 136.21, respectively. Other life table statistics were presented.     

Andes Hantavirus-Infection of a 3D Human Lung Tissue Model Reveals a Late Peak in Progeny Virus Production Followed by Increased Levels of Proinflammatory Cytokines and VEGF-A

Andes virus (ANDV) causes hantavirus pulmonary syndrome (HPS), a severe acute disease with a 40% case fatality rate. Humans are infected via inhalation, and the lungs are severely affected during HPS, but little is known regarding the effects of ANDV-infection of the lung. Using a 3-dimensional air-exposed organotypic human lung tissue model, we analyzed progeny virus production and cytokine-responses after ANDV-infection. After a 7–10 day period of low progeny virus production, a sudden peak in progeny virus levels was observed during approximately one week. This peak in ANDV-production coincided in time with activation of innate immune responses, as shown by induction of type I and III interferons and ISG56. After the peak in ANDV production a low, but stable, level of ANDV progeny was observed until 39 days after infection. Compared to uninfected models, ANDV caused long-term elevated levels of eotaxin-1, IL-6, IL-8, IP-10, and VEGF-A that peaked 20–25 days after infection, i.e., after the observed peak in progeny virus production. Notably, eotaxin-1 was only detected in supernatants from infected models. In conclusion, these findings suggest that ANDV replication in lung tissue elicits a late proinflammatory immune response with possible long-term effects on the local lung cytokine milieu. The change from an innate to a proinflammatory response might be important for the transition from initial asymptomatic infection to severe clinical disease, HPS.     

The Relationships among Transmission Frequency, Male Recombination and Progeny Production in DROSOPHILA MELANOGASTER

The T-007 second chromosome line, which was originally isolated in 1970 from a natural population of Drosophila melanogaster at Harlingen, south Texas, has previously been shown to be associated with several unusual genetic phenomena. In the present study, two characteristics, distorted transmission frequency and male recombination, were analyzed in relation to the progeny production of T-007 heterozygous individuals. The following points were established: (1) Distorted transmission frequency in the T-007 heterozygous male was mainly due to "elimination" of T-007 chromosomes among the progeny, while no such elimination occurred for the normal partner chromosome. (2) Transmission frequency and progeny production of the T-007 heterozygous females were normal, or at least almost normal. (3) The frequency of male recombination increased with an increasing degree of distortion. This was due to an increased number of recombinants produced per male and to a decreased number of progeny receiving the T-007 chromosome.     

The transmission of yeasts by Drosophila buzzatii during courtship and mating

The transmission of yeasts from generation to generation for Drosophila buzzatii was shown to occur vertically through the pupal stage and horizontally during mating. Males and females transmitted yeasts to the opposite sex most often during mating but also during courtship. Yeasts transferred from the male to the female were more often associated with the abdomens of the females, while yeasts transferred from the female to the male were associated with both the head and the abdomen of the male. Mate choice was affected by the previous yeast diet of both males and females. Yeast transmission during courtship and mating represents the potential for parental care because mate choice is affected by previous yeast diet, and progeny development is a function of the yeasts inoculated onto the larval substrate by the adults.     

Misdirection of dosage compensation underlies bidirectional sex-specific death in Wolbachia-infected Ostrinia scapulalis

Endosymbiotic bacteria of the genus Wolbachia often manipulate the reproductive system of their hosts to propagate themselves in host populations. Ostrinia scapulalis moths infected with Wolbachia (wSca) produce female-only progeny (sex chromosomes: ZW), whereas females cured of the infection by antibiotic treatment produce male-only progeny (ZZ). The occurrence of female- and male-only progeny has been attributed to the specific death of the opposite sex during embryonic and larval development. In this bidirectional sex-specific lethality, embryos destined to die express a phenotypic sex opposite to their genotypic sex. On the basis of these findings, we suggested that wSca carries a genetic factor that feminizes the male host, the W chromosome of the host has lost its feminizing function, and discordance between the genotypic and phenotypic sexes underlies this sex-specific death. In the present study, we examined whether the failure of dosage compensation was responsible for this sex-specific mortality. Quantitative PCRs showed that Z-linked gene expression levels in embryos destined to die were not properly dosage compensated; they were approximately two-fold higher in the male progeny of wSca-infected females and approximately two-fold lower in the female progeny of infected-and-cured females. These results support our hypothesis that misdirection of dosage compensation underlies the sex-specific death.     

On the Genetic Control of Genes Located in the Sex-Chromosome Heterochromatin of DROSOPHILA MELANOGASTER

The genetic properties of a recessive autosomal point mutant, "daughterless" (symbol: da), are described. They are: (1) da maps in the euchromatin of 2L at about position 39 on the genetic map and between 27D and 31E on the salivary map; (2) when homozygous in females, da causes the production of unisexual male progenies owing to sex differential zygote mortality in the egg stage; (3) da has no effect on the progeny of mutant males; (4) female zygotes die, while at least some male zygotes survive, irrespective of the number of Y chromosomes or the amount of X-chromosome heterochromatin carried by either the mutant female or her progeny; (5) homozygous da progeny of heterozygous parents also show sex differential survival favoring males indicating a da effect in development as well as in oogenesis, but with the developmental effect much less pronounced; (6) extra heterochromatin from either the X or Y chromosome in either the mother or her progeny can reduce the mortality caused by da in development (and, therefore, conceivably can also reduce the abnormality in oogenesis, although this is obscured by the severity of the maternal effect.)—From these results, it is suggested that (1) da regulates either the activity of structural genes in the sex chromosome heterochromatin or the activity or stability of their products, and (2) it is a defective product of sex chromosome heterochromatic genes that causes the abnormalities resulting in the observed mortality of heterozygous progeny of homozygous mutant mothers and of homozygous mutant progeny of heterozygous mothers.—The striking parallels with the properties of the gene, "abnormal oocyte" are noted as is the close linkage between the two loci. The possibility of a special sex-chromosome-heterochromatin-regulator region on chromosome 2 is considered.     

Effect of a single dose of Saccharomyces cerevisiae var. boulardii on the occurrence of porcine neonatal diarrhoea

Piglet neonatal diarrhoea is an important issue in modern pig production and is linked to increased mortality and poor growth rates, affecting long-term pig health, increasing use of medication and cost of production. Saccharomyces cerevisiae var. boulardii (SB) is a probiotic yeast with documented clinical efficacy in the prevention and treatment of diarrhoeal diseases in humans. The objectives of the current study were to evaluate the effect of SB on occurrence and severity of neonatal diarrhoea in piglets, mortality and growth rate. Forty-six litters (606 piglets) were randomly allocated to a control or SB treatment (n=23 per treatment). Within 24 h of farrowing, piglets assigned to the SB treatment received a single oral dose of a paste containing 3.3×10⁹ CFU of SB CNCM I-1079. Piglets from the control litters received a placebo paste. Piglet weight, mortality and diarrhoea were recorded up to day 7 of age. It was shown that numbers of diarrhoea days were significantly correlated with increased mortality rate and reduced weight gain (P<0.05). SB treatment had no effect on growth or mortality in diarrhoeic litters. However, SB-supplemented litters had significantly lower faecal scores, indicating firmer faeces (P<0.01) and fewer numbers of diarrhoeic days (P<0.01) during the 1^st week of life. Reduction in the number of diarrhoeic litters compared with the control group was observed following the probiotic administration (P<0.05). These results highlight the detrimental effects of neonatal diarrhoea on pre-weaning performance and suggest that SB, by reducing diarrhoea duration and severity, has the potential of improving enteric health in the early stages of life in pigs.     

Biology of Leipothrix dipsacivagus (Acari: Eriophyidae), a candidate for biological control of invasive teasels (Dipsacus spp.)

The present study describes key aspects of the biology of Leipothrix dipsacivagus, an eriophyid mite that is under study as a biological control candidate of Dipsacus fullonum and D. laciniatus (Dipsacaceae). Preliminary host-specificity tests have shown that it can develop and reproduce only on Dipsacus spp. (teasels). Studies were conducted in a laboratory at 26 ± 2^oC with 16 h of light per day. Mites for the stock colony were collected from D. laciniatus in Klokotnitsa, Bulgaria and reared on rosettes of D. laciniatus in the laboratory. Unfertilized L. dipsacivagus females reared in isolation from the juvenile stage produced male offspring only, while progeny of fertilized females were of both sexes, suggesting arrhenotokous parthenogenesis with haplodiploid sex determination. Experiments were designed to compare male progeny from fertilized females to males from unfertilized females and to compare males and females from fertilized females. Male progeny of virgin mothers had significantly longer durations of active immature stages and total egg-to-adult period than male progeny of fertilized females. Female progeny had significantly longer durations of egg incubation, active immature stages and egg-to-adult period than male progeny from fertilized mothers. Adult longevity was significantly greater in females than in males. Fertilized females produced significantly more eggs per day and overall than virgin females. The results of this study suggest that fertilization status of L. dipsacivagus females can affect both their own fecundity and the development of their male progeny.     

Male mediated caffeine effects over two generations of rats

Caffeine exposure of a male rat prior to mating affected his progeny and the progeny of a second generation. The dose chosen, 30 mg/kg per day given orally, was approximately equivalent to a caffeine intake of 10-12 cups of brewed coffee daily. In the first (F1) generation caffeine consumption of the sires for a minimum period of 15 days prior to mating with drug naive females, caused significant fetal growth retardation of both sexes and an increased postnatal mortality of pups between weeks 1 and 2, many of which displayed characteristics of runts. Persistent caffeine effects were also found in a second (F2) generation obtained by back breeding male and female F1 offspring from control and treated groups. The F2 pups of both sexes, from the female breeding line, were born significantly heavier when compared with their control counterparts. In the male breeding line, 33% of the litters conceived were aborted in utero, and among the young F2 pups born runts were again evident. At the conclusion of the breeding for the first generation the testes of the FO sires were studied after they received caffeine for 38 consecutive days. The experimental testes showed a marked degeneration characterized by significant overall size reduction, breakdown of the germinal epithelium, accumulation of cellular debris in the lumen of the seminiferous tubules, and significant reduction in the abundance of mature spermatozoa. On ultrastructural examination there appeared to be genetic damage to the spermatozoa where nucleic cysts and pouches were seen.